As is known in the art, radio frequency (RF) systems may include a transmit signal path, a receive signal path, and a common signal path used for transmit and receive. For example, an antenna may be shared between transmit and receive front ends. In such systems, it is desirable to transmit high signal levels with low loss to the antenna while protecting the receive path from high incident signal levels (e.g., signals from an jammer). To protect the receive path, it is known to use a 5-port circulator for narrowband and medium-bandwidth applications.